Question

Which of the following is a trace element required only in small amounts by most living things?

• A. Oxygen
• B. Iron
• C. Nitrogen
• D. Hydrogen

Answer 1

Answer: (B)

The correct option is B Iron
Iron is required in living forms in trace amounts, which if increased causes toxic effects. Deficiency of iron leads to anemia. The daily requirement of iron for an adult man is 8mg/day and for an adult woman is 18mg/day. Iron is important for the plants as the plants can not produce chlorophyll without the iron.